There are many situations in which auger conveyors can be very useful in view of the relatively high material conveyed to power ratio for augers. However the use of auger conveyors has many times been limited to situations where the bore in a mine in which the auger operates is linear, and/or where the mine bore itself can be effectively utilized to facilitate the conveyance. Where the bore is non-linear, or the bore is significantly larger than the auger sections, auger conveyors have not been as useful.
According to the present invention a self-propelled conveyor, and associated method of mining and conveying material, are provided which utilize the advantageous attributes of an auger in a wide variety of environments. The conveyor according to the present invention is moved under its own power into a bore toward a mine site, or the like, whether or not the bore is linear. The conveyor according to the invention can adjust to a wide variety of bends and turns, yet still effectively convey mined material.
According to one aspect of the present invention, a self-propelled conveyor is provided comprising: A plurality of auger sections, each section comprising a spiral mounted on a shaft, a housing surrounding the spiral and having two end terminations, and means for effecting driving of one spiral by driving an adjacent spiral whether or not the shafts are in line with each other. Means mounted on the auger section housings for facilitating moving the auger section housings. The end terminations allowing relative pivotal movement between adjacent housing sections, at least in a horizontal plane. And, the means for effecting driving of one spiral by driving of an adjacent spiral whether or not the shafts are in line with each other comprises axially and radially extending projections from each adjacent shaft providing a lost motion connection between the shafts. The housing end terminations preferably comprise inter-engaging cylindrical section elements allowing relative rotational movement between adjacent housing sections of at least about 15.degree. in a horizontal plane, and stop means are typically provided for preventing relative rotation beyond a certain point. Bearing means may be provided for mounting the shafts within the housings, the bearing means comprising hang it type bearings so as not to interfere with material conveyance. The drive means for effecting driving of the shafts preferably comprise a plurality of different drives one associated with every few auger sections.
The means mounted to the auger section housings for moving the auger section housings preferably continuously engage the ground. In one embodiment, such means comprise a mining chain with loose connections between links to allow the chain to follow a non-linear path, and sprockets provided at least at the front and rear of the auger sections to effect driving of the chains and thereby a crawler type advancing action of the auger sections into the mine bore. Alternatively, the moving means may comprise at least a pair of wheels mounted on an axle, such as two wheels mounted at a center section of the auger housing with a rub rail bowed outwardly at the center section so as to extend outwardly past the most outward termination of a wheel.
Two (or even more) spirals may be provided within each auger section housing, with a common drive element (e.g. rod) interconnected by a universal connection to a corresponding rod in an adjacent auger section so that driving of the spirals in one housing effects driving of the spirals in an adjacent housing.
According to yet another aspect of the present invention, a method of cutting and conveying mined material from a mine site through a non-linear bore, using a cutting head and a plurality of pivotally interconnecting auger sections is provided. The method comprises the steps of: (a) At the mine site, cutting the material to be mined with the cutting head. (b) Substantially continuously moving the auger sections into the bore toward the mine site. (c) Effecting pivotal movement of adjacent auger sections with respect to each other to conform to the non-linear bore. And, (d) continuously conveying the mined material away from the mine site by rotating the auger sections, which engage and transport the mined material, power for transmitting rotation of one auger section being transmitted to at least one adjacent auger section. Step (d) is preferably practiced by rotating every few auger sections with a power source.
Utilizing a conveyor according to the invention very high conveyance capacities can be achieved. For example for the diameters (spiral diameters) given in the table below, the indicated tons per minute of mined material can be conveyed, assuming a 100 rpm rotation of the auger spirals:
______________________________________ CONVEYOR CAPACITY DIAMETER TPM @ 100 RPM ______________________________________ 24 8.1 30 16.2 36 28.3 42 45.4 ______________________________________
The spirals typically operate 50% full (that is the housing is 50% full of coal or other mined material).
It is the primary object of the present invention to provide for the effective conveyance of mined material, or the like, through non-linear bores, with constant conveyor advancement being possible. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.